Four-effect low-temperature evaporation wastewater treatment equipment

Abstract

The utility model discloses a four -effect low temperature evaporation wastewater treatment equipment relates to low temperature evaporation wastewater treatment technical field, and the utility model discloses a treatment jar, wastewater output pipe and steam delivery pipe are equipped, and four are equipped with equidistance distribution to the treatment jar, and the upper portion of four treatment jars is provided with wastewater inlet pipe and steam inlet pipe, and the top middle part of four treatment jars is equipped with steam output pipe, and the application can carry out refrigeration to the wastewater of each level treatment completion through setting and the crystallization of saturated crystal of the crystallization jar and the refrigeration plate, and the wastewater is continuously stirred to force wastewater overall even, fast cooling, so that the impurity of dissolved state can reach supersaturation state rapidly and evenly crystallize as crystal, greatly avoided the concentrated accumulation of crystal in the tank bottom or local area, effectively reduced the possibility of crystal into the next level treatment jar, thereby protected the subsequent evaporation equipment from the risk of fouling and plugging, prolonged the service life of the whole set device.

Description

Technical Field

[0001] This utility model relates to the field of low-temperature evaporation wastewater treatment technology, specifically a four-effect low-temperature evaporation wastewater treatment device. Background Technology

[0002] In industrial production processes (such as chemical, pharmaceutical, and electronics industries), a large amount of wastewater containing high concentrations of salt, organic matter, or other soluble impurities is generated. If this wastewater is discharged directly, it will cause serious pollution to the aquatic environment. Therefore, it needs to be treated in depth before being discharged or recycled. Low-temperature evaporation technology has become one of the mainstream technologies for treating such high-concentration wastewater due to its advantages such as low energy consumption, mild operating temperature, and reduction of the decomposition of heat-sensitive impurities. Among them, multi-effect low-temperature evaporation equipment is widely used because it can realize the step-by-step utilization of heat and further reduce energy consumption.

[0003] Referring to the patent document: Patent Publication No. CN223047293U, Patent Publication Date 2025-07-01, in particular, a multi-effect evaporation crystallization wastewater treatment and recovery device is proposed. Addressing the problem that existing devices struggle to adjust the contact time between wastewater and steam according to different concentrations, making it inconvenient to effectively manage the wastewater concentration process, the device proposes the following solution: It includes multiple evaporators, each evaporator comprising a tank. One side of the tank's outer wall has a liquid inlet and an air inlet, the bottom of the tank has a liquid delivery end, and the other side of the tank's outer wall has an air outlet. Multiple sets of threaded pipes are used to increase the contact time between wastewater and steam. Water gradually evaporates to form steam, while the solute gradually concentrates. The steam and concentrated wastewater enter the interior of the next evaporator. Harmful substances in the wastewater are effectively separated during the evaporation and crystallization process, reducing environmental pollution.

[0004] Based on the search of patent numbers and the shortcomings of existing technologies, the following was found:

[0005] In actual operation, existing multi-effect low-temperature evaporation wastewater treatment equipment experiences a gradual saturation of soluble impurities in the high-concentration wastewater during the staged evaporation and concentration process, leading to crystal precipitation. Because existing equipment lacks specific pre-precipitation crystal technology, these crystals easily enter the next stage of treatment tank along with the wastewater. Furthermore, to achieve efficient heat utilization, multi-effect evaporation equipment is typically designed with a higher vacuum pressure in the subsequent treatment tank compared to the preceding stage. This results in a lower boiling point for the wastewater in the subsequent stage, making crystal precipitation even easier. These crystals adhere to the inner wall of the treatment tank, pipe interfaces, or the surface of the evaporation components. Over long-term operation, this can easily cause pipe blockage, reduced evaporation efficiency, and even require shutdown for disassembly and cleaning, severely impacting the stability of continuous operation and shortening the equipment's lifespan.

[0006] Therefore, this utility model provides a four-effect low-temperature evaporation wastewater treatment device. Utility Model Content

[0007] To address the problem that existing multi-effect evaporation equipment lacks a crystal pretreatment device, causing crystals in saturated wastewater to directly enter and adhere to the subsequent effect units, which have higher vacuum levels and are more prone to scaling, resulting in frequent blockages, efficiency reduction, and maintenance downtime, this utility model aims to provide a four-effect low-temperature evaporation wastewater treatment device.

[0008] To achieve the above objectives, this utility model provides the following technical solution: a four-effect low-temperature evaporation wastewater treatment device, comprising treatment tanks, wastewater output pipes, and steam conveying pipes. The treatment tanks are arranged at equal intervals. Each of the four treatment tanks has a wastewater inlet pipe and a steam inlet pipe at its upper part. A steam output pipe is located at the center of the top of each of the four treatment tanks. The two ends of the steam conveying pipe are flanged and connected to the ends of the steam inlet and steam output pipes. A precipitation mechanism is located in the center of each of the four treatment tanks to remove crystalline impurities from the wastewater. The precipitation mechanism includes:

[0009] The mixing assembly includes a precipitation tank that is installed on one side of the treatment tank and is used in a one-to-one correspondence with it. Each precipitation tank is located between every two treatment tanks. A wastewater output pipe is fixedly installed at the bottom center of the treatment tank. The other end of the wastewater output pipe is fixedly installed on the upper side of the precipitation tank. A tee pipe is fixedly installed at the bottom of the wastewater output pipe. Control valves are fixedly installed on both sides of the tee pipe. A wastewater conveying pipe is fixedly installed at one end of the tee pipe, and the other end of the wastewater conveying pipe is fixedly installed at one end of the wastewater inlet pipe.

[0010] A rotating ring is rotatably installed on the upper part of multiple precipitation tanks. A rotating rod is slidably locked in the middle of the rotating ring. A driven gear is fixedly installed on the outer side of the rotating rod. Multiple sets of transmission rods are movably installed on the outer side of the rotating rod. A scraper is movably installed on the other end of the multiple sets of transmission rods. A drive assembly is provided on one side of the driven gear. Two symmetrically distributed cooling plates are fixedly installed in the middle of the shell of the precipitation tank. A frame is fixedly installed in the middle of the top of the precipitation tank.

[0011] The scraping assembly, located at the top of the frame, is used to adjust the position of the scraper.

[0012] Preferably, the scraping assembly includes a cylinder fixedly mounted on one side of the top of the frame, and the top of the rotating rod is rotatably mounted on the drive end of the cylinder.

[0013] Preferably, the drive assembly includes a servo motor fixedly mounted on the other side of the top of the frame, and a drive gear is fixedly mounted on the drive end of the servo motor, with the drive gear and the driven gear meshing with each other.

[0014] Preferably, a rubber plate is fixedly installed on one side of each of the plurality of scrapers, and the rubber plate is in contact with the inner wall of the precipitation tank.

[0015] Preferably, each of the scrapers has a slider fixedly installed at its top, and the upper inner wall of the precipitation tank has three grooves that cooperate with the sliders.

[0016] Preferably, two symmetrically distributed drive rods are fixedly installed on the outer surface of the rotating rod, and both drive rods are slidably engaged in the middle of the rotating ring.

[0017] Beneficial effects

[0018] This invention provides a four-effect low-temperature evaporation wastewater treatment device. Compared with the prior art, it has the following advantages:

[0019] 1. This application, by setting up a precipitation tank and a cooling plate, can cool the wastewater after each stage of treatment, causing it to precipitate saturated crystals. Simultaneously, combined with a stirring assembly, a servo motor drives the active and driven gears to rotate the rotating rod, which in turn causes multiple sets of transmission rods and scrapers to rotate synchronously, continuously stirring the wastewater. This, in conjunction with the cooling plate on the precipitation tank wall, forces the wastewater to cool down uniformly and rapidly, breaking down temperature stratification. This allows dissolved impurities to quickly reach a supersaturated state and precipitate uniformly as crystals, greatly avoiding the concentrated accumulation of crystals at the bottom of the tank or in localized areas. This effectively reduces the possibility of crystals entering the next stage of treatment, thus protecting subsequent evaporation equipment from scaling and clogging, and extending the service life of the entire system.

[0020] 2. This application uses a transmission rod to drive the scraper to retract or expand. In stirring mode, the scraper retracts to stir the fluid only. In scraping mode, the scraper expands outward until the rubber plate on the side is in close contact with the inner wall of the precipitation tank. Then, driven by the rotating rod, it rotates, which can efficiently and thoroughly scrape off the crystal layer attached to the inner wall of the tank. This allows it to clean the crystals on the inner wall of the precipitation tank while protecting the precipitation tank, preventing the precipitation tank from being worn by friction for a long time and affecting its use. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of this utility model.

[0022] Figure 2 This is a schematic diagram of the precipitation mechanism of this utility model.

[0023] Figure 3 This is a schematic diagram of the cross-sectional structure of the precipitation tank of this utility model.

[0024] Figure 4 This utility model Figure 3 Enlarged view of point A in the middle.

[0025] Figure 5 This is a schematic cross-sectional view of another precipitation tank according to the present invention.

[0026] In the diagram: 1. Treatment tank; 11. Wastewater inlet pipe; 111. Wastewater outlet pipe; 12. Steam inlet pipe; 13. Steam outlet pipe; 131. Steam conveying pipe; 2. Sedimentation mechanism; 21. Stirring assembly; 211. Sedimentation tank; 2111. Wastewater conveying pipe; 212. Rotating rod; 213. Scraper; 2131. Transmission rod; 2132. Rubber plate; 2133. Slider; 214. Frame; 215. Servo motor; 2151. Drive gear; 216. Driven gear; 2161. Rotating ring; 217. T-pipe; 2171. Control valve; 218. Cooling plate; 22. Scraping assembly; 221. Cylinder; 222. Drive rod. Detailed Implementation

[0027] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0028] Please see Figure 1-5 This utility model provides a technical solution: a four-effect low-temperature evaporation wastewater treatment device, including a treatment tank 1, a wastewater outlet pipe 111, and a steam conveying pipe 131. The treatment tank 1 has four equally spaced tanks, which, from left to right, are designated as a primary treatment tank, a secondary treatment tank, a tertiary treatment tank, and a quaternary treatment tank. The later the treatment tank 1 is located, the greater the internal vacuum pressure, resulting in a lower boiling point for the wastewater. This ensures that the low-temperature steam from the previous stage can bring the wastewater in the next stage to its boiling point. The wastewater inlet pipe 11 of the primary treatment tank 1 is connected to an external sewage discharge pipeline, while the steam inlet pipe 12 is connected to an external steam conveying pipeline. The wastewater outlet pipe 111, located at the last stage, is connected to an external wastewater collection device for subsequent wastewater treatment. The upper steam outlet pipe 13 can be connected to heat recovery devices such as heat exchangers, allowing for more efficient use of the remaining low-temperature steam. Each of the four treatment tanks 1 has a wastewater inlet pipe 11 and a steam inlet pipe 12 at its upper part. A steam outlet pipe 13 is located at the top center of each of the four treatment tanks 1. The two ends of the steam delivery pipe 131 are connected to the ends of the steam inlet pipe 12 and the steam outlet pipe 13 via flanges. A precipitation mechanism 2 is located in the middle of each of the four treatment tanks 1 to remove crystalline impurities from the wastewater. The precipitation mechanism 2 includes:

[0029] The stirring assembly 21 includes a precipitation tank 211, which is disposed on one side of the treatment tank 1 and used in a corresponding manner. Each precipitation tank 211 is disposed between every two treatment tanks 1. The precipitation tank 211 is designed to precipitate crystals from the saturated wastewater liquid by lowering the temperature after each stage of wastewater treatment, thereby reducing the formation of crystals in the next stage and ensuring the long-term use of the treatment tank 1. A wastewater output pipe 111 is fixedly installed at the bottom center of the treatment tank 1. The other end of the wastewater output pipe 111 is fixedly installed on the upper side of the precipitation tank 211. A three-way pipe 217 is fixedly installed at the lower part of the wastewater output pipe 111. Control valves are fixedly installed on both sides of the three-way pipe 217. Valve 2171, the control valve 2171 is set to direct the wastewater in the precipitation pipe 211 to flow out. When the wastewater is discharged, the control valve 2171 on the side near the wastewater conveying pipe 2111 opens, while the control valve 2171 on the other side closes, so that the wastewater can enter the next stage discharge tank 1 through the wastewater conveying pipe 2111. When the crystals in the treatment tank 211 are discharged, the opening of its control valve 2171 is exactly the opposite, so that the crystals can be discharged from the other end of the three-way pipe 217. One end of the three-way pipe 217 is fixedly installed with the wastewater conveying pipe 2111, and the other end of the wastewater conveying pipe 2111 is fixedly installed at one end of the wastewater inlet pipe 11.

[0030] Multiple precipitation tanks 211 are rotatably mounted on the upper part of each tank. A rotating rod 212 is slidably mounted in the middle of the rotating ring 2161. A driven gear 216 is fixedly mounted on the outer side of the rotating rod 212. Multiple sets of transmission rods 2131 are movably mounted on the outer side of the rotating rod 212. A scraper 213 is movably mounted on the other end of the multiple sets of transmission rods 2131. A drive assembly is provided on one side of the driven gear 216. Two symmetrically distributed cooling plates 218 are fixedly mounted in the middle of the shell of the precipitation tank 211. A frame 214 is fixedly mounted in the middle of the top of the precipitation tank 211. The rotation of the driven gear 216 drives the rotating ring 2161 to rotate. Under the limiting drive of the drive rod 222, the rotating rod 212 can be driven to rotate, so that the transmission rod 2131 and the scraper 213 rotate synchronously. This can stir the wastewater in the precipitation tank 211, so that it can be uniformly cooled under the action of the cooling plate 218 to precipitate the saturated crystals inside.

[0031] The scraping assembly 22 is located on the upper part of the frame 214 and is used to adjust the position of the scraper 213.

[0032] The scraping assembly 22 includes a cylinder 221 fixedly installed on one side of the top of the frame 214. The top of the rotating rod 212 is rotatably installed on the drive end of the cylinder 221. The cylinder 221 is an SMC standard cylinder model JMDBB32-50-M9BW. Driven by the cylinder 221, the rotating rod 212 can be moved downward, so that in cooperation with the transmission rod 2131, the scraper 213 can be moved inward to stir the wastewater in the precipitation tank 211, so that it is cooled evenly and impurities are precipitated, or it can be expanded outward to contact the inner wall of the precipitation tank 211 and scrape off the crystals attached to the inner wall of the precipitation tank 211.

[0033] The drive assembly includes a servo motor 215 fixedly mounted on the other side of the top of the frame 214. The drive end of the servo motor 215 is fixedly mounted with a drive gear 2151. The drive gear 2151 and the driven gear 216 are meshed with each other. The servo motor 215 is an AC servo motor with model number 60TM-01330F5-C. Under its drive, it can drive the drive gear 2151 to rotate, thereby causing the driven gear 216 meshed with it to rotate.

[0034] A rubber plate 2132 is fixedly installed on one side of each of the multiple scrapers 213. The rubber plate 2132 is in contact with the inner wall of the precipitation tank 211. By setting the rubber plate 2132, the crystal is scraped by the contact between the rubber plate 2132 and the inner wall of the precipitation tank 211. At the same time, the inner wall of the precipitation tank 211 can be protected to avoid excessive wear and extend its service life.

[0035] Multiple scrapers 213 are fixedly mounted with sliders 2133 at their top ends. The upper inner wall of the precipitation tank 211 is provided with three grooves that cooperate with the sliders 2133. Both the sliders 2133 and the grooves are T-shaped structures. By setting the sliders 2133, the scrapers 213 can be limited, so that when the rotating rod 212 moves up and down, the sliders 2133 can stably drive the scrapers 213 to retract or expand through sliding in the grooves.

[0036] Two symmetrically distributed drive rods 222 are fixedly installed on the outer surface of the rotating rod 212. Both drive rods 222 are slidably locked in the middle of the rotating ring 2161. By setting the drive rods 222, the rotating rod 212 can slide up and down in the middle of the rotating ring 2161, and the rotating ring 2161 can drive the rotating rod 212 to rotate.

[0037] Furthermore, any content not described in detail in this specification is existing technology known to those skilled in the art.

[0038] During operation, the four treatment tanks 1 are arranged from left to right as primary, secondary, tertiary, and quaternary stages. The vacuum pressure inside each subsequent treatment tank gradually increases (i.e., the vacuum degree is higher). According to the principle that "the lower the pressure, the lower the boiling point of the liquid," the boiling point of the wastewater in each stage decreases, creating conditions for "low-temperature steam from the front stage to drive the evaporation of wastewater in the back stage." The wastewater in the primary treatment tank 1 enters through the wastewater inlet pipe 11 connected to an external sewage pipeline, and the steam enters through the steam inlet pipe 12 connected to an external steam source, starting the initial heating. The secondary, tertiary, and quaternary treatment tanks 1... The steam output pipe 13 at the top of the pre-treatment tank 1 is connected in series via a steam transmission pipe 131 to the steam inlet pipe 12 of the subsequent treatment tank. The waste heat from the pre-treatment tank is used to continuously heat the wastewater in the subsequent treatment tank, realizing the tiered utilization of energy. The wastewater output pipe 111 of the fourth-stage treatment tank is connected to an external wastewater collection device to discharge the final treated wastewater. The steam output pipe 13 of the fourth-stage treatment tank can be connected to a heat recovery device such as a heat exchanger to reuse the heat of the remaining low-temperature steam, such as preheating the inlet water or heating other media, thereby improving the energy utilization rate.

[0039] Each precipitation tank 211 corresponds to two adjacent treatment tanks 1. It receives wastewater from the previous treatment tank through the wastewater output pipe 111 (after the previous treatment, the wastewater contains saturated crystal impurities). The temperature is reduced by the cooling plate 218 of the precipitation tank 211, causing the crystals in the saturated wastewater to precipitate (the solute solubility decreases as the temperature decreases, and crystals precipitate). This reduces the crystal production in the subsequent treatment tank 1 and ensures the long-term stable operation of the wastewater treatment tank 1. After the crystals enter the precipitation tank 211, the servo motor 215 drives the drive gear 2151 to rotate. Through meshing with the driven gear 216, it drives the rotating ring 2161 and the rotating rod 212 to rotate. The transmission rod 2131 on the outside of the rotating rod 212 is linked with the scraper 213 to realize the stirring action. Through the rotation of the scraper 213 and the transmission rod 2131, in conjunction with the cooling plate 218 to cool the wastewater, the crystals are precipitated evenly to avoid local temperature differences that cause crystal accumulation.

[0040] The cylinder 221 drives the rotating rod 212 to move up and down. In the stirring mode, the rotating rod moves upward, and the transmission rod drives the scraper to move inward to stir the wastewater, accelerate the uniform cooling and precipitation of crystals. When the rotating rod moves downward, the transmission rod drives the scraper to move outward so that the rubber plate fits against the inner wall of the precipitation tank and scrapes off the attached crystal impurities. When the wastewater in the precipitation tank 211 is discharged, the control valve 2171 on the side near the wastewater conveying pipe 2111 is opened and the control valve 2171 on the other side is closed. The wastewater flows through the wastewater conveying pipe 2111 and the wastewater inlet pipe 11 into the next-stage treatment tank 1. When the crystals in the precipitation tank 211 are discharged, the control valve 2171 is operated in reverse, and the crystals are discharged from the other end of the three-way valve 217, completing the crystal cleaning in the precipitation tank 211.

[0041] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0042] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A four-effect low-temperature evaporation wastewater treatment device, comprising a treatment tank (1), a wastewater output pipe (111), and a steam conveying pipe (131), characterized in that: The treatment tank (1) is provided with four equally spaced tanks. Each of the four treatment tanks (1) is provided with a wastewater inlet pipe (11) and a steam inlet pipe (12) at the top. A steam outlet pipe (13) is provided at the middle of the top of each of the four treatment tanks (1). The two ends of the steam conveying pipe (131) are installed at the ends of the steam inlet pipe (12) and the steam outlet pipe (13) through flanges. A precipitation mechanism (2) is provided in the middle of the four treatment tanks (1) for removing crystalline impurities from the wastewater. The precipitation mechanism (2) includes: The stirring assembly (21) includes a precipitation tank (211) that is disposed on one side of the treatment tank (1) and used in a corresponding manner. Each precipitation tank (211) is disposed between every two treatment tanks (1). A wastewater output pipe (111) is fixedly installed at the middle of the bottom of the treatment tank (1). The other end of the wastewater output pipe (111) is fixedly installed on the upper side of the precipitation tank (211). A three-way pipe (217) is fixedly installed at the lower part of the wastewater output pipe (111). Control valves (2171) are fixedly installed on both sides of the three-way pipe (217). A wastewater conveying pipe (2111) is fixedly installed at one end of the three-way pipe (217). The other end of the wastewater conveying pipe (2111) is fixedly installed at one end of the wastewater inlet pipe (11). A rotating ring (2161) is rotatably mounted on the upper part of multiple precipitation tanks (211). A rotating rod (212) is slidably mounted in the middle of the rotating ring (2161). A driven gear (216) is fixedly mounted on the outer side of the rotating rod (212). Multiple sets of transmission rods (2131) are movably mounted on the outer side of the rotating rod (212). A scraper (213) is movably mounted on the other end of the multiple sets of transmission rods (2131). A drive assembly is provided on one side of the driven gear (216). Two symmetrically distributed cooling plates (218) are fixedly mounted in the middle of the shell of the precipitation tank (211). A frame (214) is fixedly mounted in the middle of the top of the precipitation tank (211). A scraping assembly (22) is located on the upper part of the frame (214) and is used to adjust the position of the scraper (213).

2. The four-effect low-temperature evaporation wastewater treatment equipment according to claim 1, characterized in that: The scraping assembly (22) includes a cylinder (221) fixedly mounted on one side of the top end of the frame (214), and the top end of the rotating rod (212) is rotatably mounted on the drive end of the cylinder (221).

3. The four-effect low-temperature evaporation wastewater treatment equipment according to claim 1, characterized in that: The drive assembly includes a servo motor (215) fixedly mounted on the other side of the top of the frame (214). The drive end of the servo motor (215) is fixedly mounted with a drive gear (2151), and the drive gear (2151) and the driven gear (216) are meshed and connected to each other.

4. The four-effect low-temperature evaporation wastewater treatment equipment according to claim 1, characterized in that: A rubber plate (2132) is fixedly installed on one side of each of the scrapers (213), and the rubber plate (2132) is in contact with the inner wall of the precipitation tank (211).

5. The four-effect low-temperature evaporation wastewater treatment equipment according to claim 1, characterized in that: Each of the scrapers (213) has a slider (2133) fixedly installed at its top end, and the upper inner wall of the precipitation tank (211) has three grooves that cooperate with the sliders (2133).

6. The four-effect low-temperature evaporation wastewater treatment equipment according to claim 1, characterized in that: Two symmetrically distributed drive rods (222) are fixedly installed on the outer surface of the rotating rod (212), and both drive rods (222) are slidably locked in the middle of the rotating ring (2161).

Images